[Libav-user] Translating working command line to programmatic code

[Robert Krüger]

Hi,

On Thu, Aug 2, 2012 at 10:06 PM, Brad O'Hearne
<brado at bighillsoftware.com> wrote:
> Hello,
>
> I could use a little guidance from the ffmpeg gurus on the list here. The
> short summary of my request is that I have a working ffmpeg command line
> which proves my use case, and now I need to convert that to programmatic
> code and integrate it into a app. Details:
>
> *** My use case:
> On a Mac, I need to capture video from an attached camera (such as the
> internal MacBook Pro camera), transcode it to FLV, and then stream (publish)
> it to Wowza media server for restreaming.
>
> *** What I have done so far:
> I have successfully used the ffmpeg client to take an mp4 video, transcode
> it to FLV, and publish it to Wowza using RTMP, using the following command
> line:
>
> ffmpeg -i ~/SampleVideo.mp4 -re -r 24 -b:v 1000k -f flv
> rtmp://localhost/live/SAMPLE_STREAM
>
> I have also consumed the video from a web browser successfully, so I know
> that this is both possible in ffmpeg and works. Basically the above serves
> as a successful prototype for my use-case.
>
> *** What I need to do now:
> I need know how to do two things specifically:
>
> 1) Convert the above command line to programmatic code which uses the
> underlying ffmpeg libraries to accomplish the same thing. Can anyone point
> me in the right direction of which libraries to use, and or direct me to a
> snippet of sample code which demonstrates how to do this?
>
> 2) Whatever the approach in 1 above, I need to convert from taking a video
> file as input, and instead taking captured frame data as input.
>
> Any help with these two things would be greatly appreciated.
>
> Cheers,
>
> Brad
>
> Brad O'Hearne
> Founder / Lead Developer
> Big Hill Software LLC
> http://www.bighillsoftware.com
>
> _______________________________________________
> Libav-user mailing list
> Libav-user at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/libav-user
>

start with the examples in doc/examples and then go through the source
code of ffmpeg.c to see what happens for your specific command line.
Either use a debugger to see what values are set for codec contexts or
format context in your case or put your own debug output there.

HTH,

Robert